- BaseX-Talk - mailman.uni-konstanz.de

Write several XML files via one XQuery
by Brune, Nicole 01 Mar '21

01 Mar '21

Dear all, please excuse me if this has been covered in the documentation and I just haven't found it. I am trying to harvest some information from XML files in a database (all XML files) and create several new XML files with the information. I am aware of the function write:file(path, data). Is it possible to write several files in one go and via one XQuery? I have tried exchanging "../test.xml" with "../test[1 to 2000].xml, ..." but, unfortunately, it did not work. Thank you kindly in advance for your help! Best, Nicole

2 1

BaseX 9.5: The Spring Edition
by Christian Grün 25 Feb '21

25 Feb '21

Dear all, we are more than happy to provide you with a new and fresh version of BaseX, our XML framework, database system and XQuery 3.1 processor: https://basex.org/ BaseX is getting faster and faster! We have spent most of our time on query rewritings and optimizations, which will speed up the execution of your XQuery code and RESTXQ apps. You can find various other new enhancements in our release: RESTXQ - the client IP address behind a proxy is added to the logs - stack traces in the error message can now be suppressed - the default error code has been changed from 400 to 500 - error messages are more user-friendly now (#1708) - content negotiation was improved (#1991) - inline arguments of called function (#1982) XQUERY FUNCTIONS - Utility: new functions for sequences, arrays and maps - Higher-Order Functions: hof:drop-while - Jobs: More options for job intervals XQUERY PERFORMANCE - revised scoring propagation (all items will take less memory) - default function inlining limit reduced from 100 to 50 - axis path rewritings, better typing (#1910, #1976, #1979) - better typing (#1906, #1908, #1909, #1944, #1945) - faster data()/string() checks (#1975) - rewrite map:merge to map:put (#1969) - rewrite order by to fn:sort (#1966) - rewrite group by to fn:distinct-values (#1932) - rewrite quantifiers to FLWOR expressions (#1961) - optimizations of arithmetic expressions (#1938, #1972) - optimizations of lookup operator (#1929, #1984) - optimizations of counts (#1965, #1973, #1974) - optimizations of regular lists (#1919, #1924) - optimizations of switch expression (#1920) - optimizations of instance of (#1939) - distinct values (#1930, #1967) - positional checks (#1937) - existence checks (#1971) For a more comprehensive list of added and updated features, check out our documentation (docs.basex.org) and check out the GitHub issues (github.com/BaseXdb/basex/issues) Have fun, Your BaseX Team

3 2

BaseX, xinclude and xpointer
by pascaljoubaud＠gmail.com 19 Feb '21

19 Feb '21

Hello BaseX-Community, I'm a beginner with baseX so my questions may sound a bit weird. I hope not too much. I have a problem using xinclude in a baseX database. Basically i have a main file which contains this xinclude instruction : <xi:include href="EP15.xml" xpointer="element(EP15)"><xi:fallback><p>Pièce non encodée pour le moment.</p></xi:fallback></xi:include> In my baseX database i have my main file and the EP15.xml file which contains this instruction : <div type="Piece" xml:id="EP15">blabla<div> When i 'm looking to my main file in base X, i always have the fallback instruction displayed : <p>Pièce non encodée pour le moment.</p> I'm using baseX 9.3.2., the local option XINCLUDE is turned on. I have also tried to use direct xpath instead of a named element in my xpointer xpointer="element(/TEI/text/body/div[1])"> but the resultat is stille the same I'm a bit stuck at the moment.. Any help would be very much appreciated ! Thanks a lot Pascal

2 10

Nasty trap with RESTXQ content negotiation
by Marco Lettere 19 Feb '21

19 Feb '21

Dear all, First of all, I hope everything is fine and all of you are staying healthy! When I read again the docs about Content Negotiation in RestXQ I noticed the sentence: Functions can be restricted to specific Media Types. The default type is|*/*|. So I wrote the two RestXQ signaures [1] with the expectation of *fallback()* behaving as a catch-all for mime-types not declared in *specific(**)*. At that point, when calling the service with something stating "Content-Type: application/xml" BaseX yields the following error: Stopped at /....: [basex:restxq] Several functions found for path "test": - ccp_ui:test [text/plain] - ccp_ui:test2 [text/plain] If I specify an explicit %rest:consumes("*/*") in the annotations of fallback(), specific() correctly intercepts the request. Unfortunately at that point calling with "Content-Type: text/plain" which should slip through the functions and be catched by fallback() yields instead: No function found that matches the request. So there is no combination, to my knowledge, to implement my use-case correctly ... besides handling mime-types explicitly in code (which is rather uncomfortable). I'm using BaseX 9.4.5 at the moment. Do you have any hint on this? Thank you very much. Marco. [1] declare %rest:path("test") %rest:POST("{$body}") %rest:consumes("text/csv", "application/xml", "application/json") %output:method("text") function s:specific($body as document-node()) { "Treated as document" }; declare %rest:path("test") %rest:POST("{$body}") %output:method("text") function s:fallback($body as item()) { "Treated as binary" };

2 2

vanishing whitespace with fn:doc()
by Jos van den Oever 17 Feb '21

17 Feb '21

Dear all, First off: BaseX is great to work with. I use it for a few statically generated websites. But I recently found what might be a bug. Some whitespace vanishes when loading xml files. E.g. this xml file: ```test.xml <a> a b <a> c </a> d e </a> ``` run like this: doc('test.xml') gives: <a>a b<a>c</a>d e</a> But running this: ``` parse-xml('<a> a b <a> c </a> d e </a>') ``` retains the whitespace. I've tested this with BaseX 7.0, 8.0, 9.0 and 9.4.6. Running this in saxon-he-10.3.jar retains the whitespace. I can work around this issue by placing xml:space="preserve" in the document element. I cannot come up with a scenario in which discarding whitespace during is parsing is ok when no DTD or XML Schema is provided. Best regards, Jos

2 7

Re: [basex-talk] Jobs and file modules
by Christian Grün 16 Feb '21

16 Feb '21

There may be various solutions ;) A minimized code example that demonstrates your procedure could be helpful here. On Tue, Feb 16, 2021 at 3:21 PM Tim Thompson <timathom(a)gmail.com> wrote: > > Yes, the insert operations also involve lookups against a couple of full-text indexes (using ft:search()). The entries in the full-text indexes include corresponding unique identifiers (URIs). The query: > > iterates through a set of library catalog records > filters on certain elements > runs full-text lookups on the text (which are name or subject strings) > inserts a new element containing the URI from a match in the index. > Logs the result of the each lookup (using file:append-text-lines()) > > > I'm guessing that the index access is what slows things down the most. What would be the approach for combining updates? > > Thank you, > Tim > > > -- > Tim A. Thompson > Discovery Metadata Librarian > Yale University Library > > > > On Tue, Feb 16, 2021 at 4:53 AM Christian Grün <christian.gruen(a)gmail.com> wrote: >> >> Hi Tim, >> >> > Is it possible to put updating expressions in a library module function (with the name of the database hard coded) and then call from the function within jobs:eval() in a main module? >> >> Yes, it should be. Here’s a little example (create database 'x' first): >> >> lib.xqm: >> module namespace lib = 'lib'; >> declare %updating function lib:delete() { >> prof:sleep(1000), >> delete node db:open('x')//x >> }; >> >> query.xq: >> let $id := jobs:eval(" >> import module namespace lib='lib' at 'lib.xqm'; >> lib:delete() >> ") >> return (prof:sleep(500), jobs:list-details($id)) >> >> The query result looks something like this: >> >> <job id="job29" type="QueryJob" state="running" user="admin" >> duration="PT0.498S" reads="(none)" writes="x" >> time="2021-02-16T10:40:57.605+01:00">import module namespace lib='lib' >> at 'lib.xqm'; lib:delete()</job> >> >> If the name of the database is found in the "writes" attribute, you’ll >> know that only this database will be write-locked. >> >> However, please note that, due to random file access patterns, >> parallel writes are often slower than consecutive ones (even with >> SSDs), so my guess is that you won’t save a lot. >> >> 48 hours sounds a lot indeed. It’s usually much, much faster to run a >> single XQuery expression that performs 1000 updates than running 1000 >> independent queries. Could you give us more information on the insert >> operations you need to perform? Is there any chance to combine >> updates? >> >> Best, >> Christian

1 0

Jobs and file modules
by Tim Thompson 16 Feb '21

16 Feb '21

Hello, I was experimenting with the jobs module and wondering why there's a difference between *file:write() *and *file:write-text()* in the query below: for $i in 1 to 5 return ( jobs:eval(' declare variable $iter external; file:write-text("~/Desktop/job"|| $iter ||".txt", (prof:sleep(5000), string(current-dateTime()))) ', map {"iter": $i} ) ) With *file:write-text()*, if I don't wrap *current-dateTime()* in *string()*, nothing is written and no files are created. With *file:write()*, text is always written and files always get created. Thanks! Tim -- Tim A. Thompson Metadata Librarian Yale University Library

2 6

Feature requests: Backups, Indexes, Execution Times
by BIRKNER Michael 12 Feb '21

12 Feb '21

Hello BaseX-Community, I am working a while with BaseX now and I like it very much. I think it is a great piece of software ... and it's Open Source ... WOW!!! But every now and then I discover some small cumbersome issues that could maybe solved with some new functionalities. That is why I would like to propose the following features for BaseX: * Description for database backups: Right now, the titles of database backups are like "dbname-2021-02-02-17-45-44". It would be great if one could add a description to such a backup. The reason is: While developing I often update databases step by step and in between these steps, I make backups of the whole database, so in case of errors or if I have to look up something, I could revert to a former state of the database. With a meaningful description, it would be much easier to pick the right backup. * RegEx in index searches: It would be great to have the possibility to search for RegEx patterns in the index, e. g. like this: db:text("db-name", "REGEX-PATTERN-HERE") or db:attribute("db-name", "REGEX-PATTERN-HERE") * Index searches with a path: I sometimes had the need to do an index search within only a certain path, e. g.: db:text('db-name', '/PATH/WITHIN/DB', 'search-word') I don't know if this is even possible to realize, but if yes, it would sometimes be very useful to me. * Selective indexing based on attribute values: It would be great to have selective indexing based on attributes and their values. Imagine an XML structure like this: <items> <item name="id">ABC</item> <item name="title">XYZ</item> <item name="person">Jane Doe</item> ... </items> If one would like to index e. g. only the ID values, a functionality to do selective indexing just for "<item>" nodes with attribute "name" that contains the value "id" would be useful. This would allow to have a comparatively small index for very large XML data sets, which could have impact on query performance. * Human readable execution times in GUI: Maybe a small change but - at least in my case - it would make developing performant xQueries much easier: Having the "Timing" section in the Info-View of the GUI display human readable times. Right now, the values are displayed only in milliseconds like 175713.28 ms. But an additional display in a more human readable format, e. g. hh:mm:ss.ms would sometimes be very useful. I hope at least some of the mentioned features do make sense and will be considered for implementation [:-)] Best regards, Michael Dieses Mail ist ausschließlich für die Verwendung durch die/den darin genannten AdressatInnen bestimmt und kann vertrauliche bzw rechtlich geschützte Informationen enthalten, deren Verwendung ohne Genehmigung durch den/ die AbsenderIn rechtswidrig sein kann. Falls Sie dieses Mail irrtümlich erhalten haben, informieren Sie uns bitte und löschen Sie die Nachricht. UID: ATU 16209706 I https://wien.arbeiterkammer.at/datenschutz

3 4

xquery:eval() required in replace()?
by Graydon Saunders 06 Feb '21

06 Feb '21

Hello -- So as part of building tests, I'm regularizing the text contents of some Word documents into single strings. (Which makes it relatively easy to make sure no words have gotten lost or changed order when compared to other stages of the process.) Regularization is a tactful way to put this particular atrocity: let $stringTidy as function(xs:string+) as xs:string := function($in as xs:string+) as xs:string {$in => string-join(' ') => replace(xquery:eval($menuMatch),'') => replace('
',' ') => replace('	',' ') => replace('',' ') => replace('\p{Zs}',' ') => replace(' +',' ') => replace(' ([,\.;:])','$1') => replace('^ ','') => replace(' $','')} $menuMatch gets stripped out of the Word because it's added by processing, rather than being present in the source file which generates the other half of the compare. (It's currently U+1405, ᐅ, though I devoutly hope this doesn't matter!) It gets read from an XSL source document, which I've included in minimal form, along with some sample data and a minimal-ish query. If I use $menuMatch in the replace, it doesn't work, in the sense that the ᐅ character is NOT removed from the string. If I xquery:eval() it, as here, the replace does work to remove the ᐅ from the string. I don't expect to need xquery:eval to use a variable as the second argument of replace(). Am I wrong? Has the pile of arrow operators exceeded the bounds of reason? Thanks! Graydon

3 2

Re: [basex-talk] FLOATS
by Christian Grün 06 Feb '21

06 Feb '21

Hi Adam, It’s recommendable to use xs:decimal instead of xs:float. Here’s one solution… declare function local:sumVec($seq) { let $count := max(($seq ! string() ! replace(., '[^_]', '') ! string-length())) + 1 let $sums := ( for $c in 1 to $count return sum( for $item in $seq let $tokens := tokenize(string($item), '_') return try { xs:decimal($tokens[$c]) } catch * { 0 } ) ) return string-join($sums, '_') }; …and another one (presumably more cryptic): declare function local:sumVec($seq) { let $numbers := ( for $item in $seq return array { for $token in tokenize(string($item), '_') return try { xs:decimal($token) } catch * { 0 } } ) return string-join( for $c in 1 to max($numbers ! array:size(.)) return sum($numbers[array:size(.) >= $c]?($c)) , '_') }; Hope this helps, Christian

1 0